Abstract：
Addressing the challenge of accurately monitoring polycyclic aromatic hydrocarbons (PAHs) in aquatic systems, this study employed diffusive gradients in thin-films (DGT) technique to achieve methods detection limits as low as 0.02 ng L-1 to 0.05 ng L-1 through in situ preconcentration and determination of time-integrated concentrations. The efficacy of the developed DGT samplers was validated under diverse environmental conditions, demonstrating independence from factors such as pH (5.03-9.01), dissolved organic matter (0-20 mg L-1), and ionic strength (0.0001-0.6 M). Notably, the introduction of a novel theoretical approach to calculate diffusion coefficients based on solvent-accessible volume tailored for PAHs significantly enhanced the method\'s applicability, particularly for organic pollutants with low solubility. Field deployments in coastal zones validated the DGT method against traditional grab sampling, with findings advocating a 4 to 7-day optimal deployment duration for balancing sensitivity and mitigating lag time effects. These results provide a sophisticated, efficient solution to the persistent challenge of monitoring hydrophobic organic pollutants in aquatic environments, broadening the scope and applicability of DGT in environmental science and providing a robust tool for researchers.
摘要：
应对准确监测水生系统中多环芳烃（PAHs）的挑战，这项研究采用薄膜（DGT）技术中的扩散梯度，通过原位预浓缩和时间积分浓度的测定，使方法的检出限低至0.02ngL-1至0.05ngL-1。在不同的环境条件下验证了开发的DGT采样器的功效，证明独立于pH（5.03-9.01）等因素，溶解的有机物（0-20mgL-1），和离子强度（0.0001-0.6M）。值得注意的是,引入一种新的理论方法来计算扩散系数的基础上的溶剂可及体积为PAHs定制显著增强了该方法的适用性，特别是对于溶解性低的有机污染物。在沿海地区的现场部署验证了DGT方法与传统的抓取采样，研究结果主张4至7天的最佳部署持续时间，以平衡敏感性并减轻滞后时间效应。这些结果提供了一个复杂的，有效解决水环境中疏水性有机污染物监测的持续挑战，扩大DGT在环境科学中的范围和适用性，并为研究人员提供强大的工具。
